I posted this thread in the Theravada forum but now think it's probably more relevant to this forum.

I’m thinking about using the inner stillness/peace as my meditation object during daily life, instead of the postures/activities. The point is to try to achieve/maintain a state of mind in stillness free from delusions and cravings, and free from fabrications (somewhat like returning to the original nature) at all possible times of daily life. If the stillness can be achieved, then fine; if not, then recollect the stillness to achieve it. I thought it would be more effective to watch the mind than to watch the postures for achieving "disenchantment, dispassion, cessation, stilling, direct knowledge, self-awakening, and liberation".

When the six senses are not pinched by the sense objects, I can remain focused on the inner quietness/stillness.

When the six senses are pinched by the sense objects (e.g. wondering thoughts), I can contemplate anicca/dukkha/anatta of these sense objects, and meanwhile reflectively contemplate the peace of the pure mind. So the sense objects can be dropped from the mind with disenchantment and dispassion while the mind can maintain the peace, untouched by the sense objects, without likes or dislikes of them.

I tried this method (experiencing stillness of mental fabrications) during sitting meditation this morning, and entered into a state of stillness/emptiness with no sense of the body for a very short while -- I'm not quite sure if it's a good state or not. It's not accompanied by piti and sukha, neither by a luminous alert mind.

This idea is related to the Patriarchal Chan [祖師禪, sometimes translated into Tathagata Chan 如来清静禅] of Master Huineng (the Sixth and Last Patriarch of Chán Buddhism). As a beginner, I don't really know the Patriarchal Chan. I'd like to learn about it and would appreciated information about it.

§10. One thing — when developed & pursued — leads solely to disenchantment, to dispassion, to cessation, to stilling, to direct knowledge, to self-awakening, to Unbinding. Which one thing? Recollection of stilling. This is one thing that — when developed & pursued — leads solely to disenchantment, to dispassion, to cessation, to stilling, to direct knowledge, to self-awakening, to Unbinding.— AN 1.287-296

I do think you're on to something, although your explanation was too technical for Chan/Seon.

However, inner peace sometimes isn't a good meditation object because that is the one place where there often isn't peace. However, in my experience the peace outside can restore inner peace when it is lost.

I've noticed that there is peace almost everywhere at all times. I'll elaborate if you want me to (but you'll have to ask), but will give you two quick examples. In the picture below it looks, at first glance quite busy and noisy and probably not a good place to find outer peace. However, look again and you'll notice over half the space is empty, everyone is friendly and no one is bothering the person taking the photo. If that isn't outer peace I don't know what is. The second example was at work where one of the pupils was shouting at me and instead of noticing his anger I looked behind him where there was a whole corridor of empty space - again more peace! There is always peace.

So don't forget, even when your meditation object (inner peace) seems temporarily missing one can find outer peace. And if you can use the outer peace to inform the inner peace you're on to a winner.

Patriarch Chan and Tathagata Chan are two different terms and they're not used as equals. In the Platform Sutra there's only talk of Tathagata Chan and no mention of Patriarch Chan (first mentioned in a story involving Yangshan Huiji and Xiangyan Zhixian - according to Jiang Wu). As for their meaning, it depends on where you look, so let's just put that aside.

If you want to focus on an inner stillness to attain stillness, well, it is a bit confusing. If there is stillness you don't have to achieve it. If there is no stillness you can't focus on it. Being free from attachments is the goal of the path which can be practised very well by cultivating samadhi and prajna. As for how, I assume that's what you're asking about. If it is Chan you want to do you should learn the huatou method so then you can carry around your question as a point of focus. What seems closer to your intentions is the mozhao (silent illumination) of which you can read here a bit.

"There is no such thing as the real mind. Ridding yourself of delusion: that's the real mind."(Sheng-yen: Getting the Buddha Mind, p 73)

I do not want to dissuade you and I do not want to imply that it is Satipatthana what you are talking about. Just want to highlight some aspects that do not appear very different from Satipatthana to me.

starter wrote:I’m thinking about using the inner stillness/peace as my meditation object during daily life, instead of the postures/activities. ... If the stillness can be achieved, then fine; if not, then recollect the stillness to achieve it.

The second sentence makes it appear as if it is Satipatthana with regard to mind. Isn't it? If you select one object there has to be mindfulness not to stray from this object. And how do you notice straying from this object? You notice it through discerning qualities that are other than this object. And if the object is "inner stillness" then what is not stillness? It is lustfullness, anger, delusion, narrowness, and such a mind is surpassable, unconcentrated and unliberated.And through discerning these non-stillness qualities the nature of arising, and passing away may be discerned too. Why? Because this is an aspect of stillness, isn't it?

starter wrote:I thought it would be more effective to watch the mind than to watch the postures for achieving "disenchantment, dispassion, cessation, stilling, direct knowledge, self-awakening, and liberation".

But even if you watch the "inner stillness" during daily life there are the activities of daily life. you cannot sit still all day long, right? Therefore somehow you have to be mindful of these activities too because if you are not then you cannot act properly in daily life. From my perspective you will necessarily come back to Satipatthana of activitites and postures etc., i.e. aspects/foundations of Satipatthana other than this "stillness" (of mind).The question perhaps is: What quality (i.e. "object") lends itself to be conjoined with mindfulness of activities and postures. Is it "stillness"? What is this ... "inner stillness"?